All participants completed incremental peak AC and FES testing to volitional exhaustion. For the peak AC test, subjects cranked a Monark 881 arm ergometer that maintained the subject at 50 revolutions per minute throughout the test. Power output progressively increased 10 watts (W) per each 3-minute stage. The peak FES test used a commercial system (Parastep-1) that was controlled independently by the subject. The process involved a series of 10-meter walking bouts of approximately 2 minutes duration at a consistent pace that was increased by the subject for each bout. Open-circuit spirometry (Horizon MMC) and Borg's rating scale (RPE) were used in both tests to assess metabolic activity and perceived exertion, respectively. Heart rate was monitored by a 12-lead electrocardiography (Cardimax) during the AC test. During the FES test, it was assessed via manual palpation.Repeated measures of variance (ANOVA) were used to compare the total duration of testing and the subjects' RPE responses between test modes, as well as to compare the peak physiological responses of each mode, including VO2, VCO2, respiratory exchange ratio (R), minute ventilation (VE), and tidal volume (VT). One-way ANOVA was used to compare heart rate values between AC and FES.